Coupler keyslot bearing contour

ABSTRACT

An improved keyslot bearing contour for a railroad coupler shank is disclosed. The keyslot contour comprises a plurality of arcs which are designed to minimize localized bearing on the keyslot during angular pull of the coupler. The improved keyslot contour is formed by a first arc, rearwardly extending towards the butt end of the coupler, which terminates in a plurality of second arcs located at each side of the coupler in proximity to the intersection of the keyslot with the side walls of the coupler.

I United States Patent l 13,568,857

[72] Inventor Russell GeorgeAltherr [56] I References Cited 10005Prudential Pl za, h g UNITED STATES PATENTS 6060! 1,609,166 11/1926l-laseltine 213/64 1 rm- 838,776 2,019,311 10/1935 Kinne 213/50 1 PM Y2,724,513 11/1955 Willison... 213/50 1 Patented Mar-19,19 1 2,889,9396/1959 Metzger 213/64 [54] COUPLER KEYSLOT BEARING CONTOUR [50] Field ofSearch Primary Examiner-Drayton E. Hoffman Attorneys-Walter L. Schlegel,Jr. and Norvell Von Behren ABSTRACT: An improved keyslot bearing contourfor a railroad coupler shank is disclosed. The keyslot contour comprisesa plurality of arcs which are designed to minimize localized bearing onthe keyslot during angular pull of the coupler. The improved keyslotcontour is formed by a first are, rearwardly extending towards the buttend of the coupler, which terminates in a plurality of second arcslocated at each side of the coupler in proximity to the intersection ofthe keyslot with the side walls of the coupler.

COUPLER KEYSLOT BEARHNIG CONTOUR BACKGROUND OF THE INVENTION Thisinvention relates generally to railroad couplers and more particularlyto an improved coupler keyslot bearing contour which minimizes localizedkeyslot bearing during angular pulling on the coupler.

In a standard railroad-type Ecoupler having a horizontal key, the keybearing surface of the coupler is generally cylindrical shaped and islocated with its axis perpendicular to the longitudinal axis of thecoupler shank. Under service buffing conditions the load on the coupleris transmitted through the butt end of the coupler with the keyremaining unloaded.

Under service pulling conditions, the load is transmitted to the yokeand draft gear through the key. When the coupler is straight, this loadis distributed over the entire length of the cylindrical key bearingsurface. However, when the coupler is horizontally angled, the key isalso angled in the coupler shank keyslot resulting in the load beingtransmitted on a corner of SUMMARY OF THE INVENTION The presentinvention overcomes the beforementioned difficulties and limitations byproviding an improved coupler keyslot bearing surface which minimizesthe localized bearing on the keyslot bearing surface during an angularpull on the coupler.

Accordingly, it is the object of the invention to provide a new andnovel improved coupler keyslot bearingcontour for a railroad. couplershank which provides substantially constant stress patterns to minimizelocalized bearing on the keyslot bearing surface during angular pull onthe coupler.

Another object of the invention is to provide new and novel improvedcoupler keyslot bearing contour having an improved bearing surface bymeans of the use of a plurality of intersecting arcs formed in thekeyslot.

These and other objects and advantages of the invention will becomeapparent from a study of the attached drawings and from a reading of thedescription of the preferred embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view, shown partiallyin section, of a standard-type railroad E-coupler in a horizontallyangled buffing position;

FIG. 2 is a plan view, shown partially in section, of a standard-typerailroad E-coupler in a horizontally angled pulling position;

FIG. 3 is a partial sectional view of the butt end of the coupler shankshowing one embodiment of the improved keyslot bearing contour of theinvention;

FIG. 4 is an enlarged sectional view of FIG. 3 showing the intersectionof the keyslot bearing surface with the side walls of the coupler shank;and

FIG. 5 is a side elevational view of the butt end of the coupler shankshowing the keyslot of FIG. 3 with the means for forming a plurality ofhereinafter described second arcs.

FIG. 6 is an enlarged sectional view of a modification of the improvedkeyslot bearing contour of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now more particularlyto the drawings, there is shown generally at 10 a standard-type railroadE-coupler which comprises a coupler head 12 having attached thereto acoupler shank 14 which terminates at the butt end 16 of the coupler 10.The butt end 16 of the coupler 10 contains a horizontal keyslot 18designed to receive a load transmitting key 20. When the coupler 10 isunder the buffing condition, as shown in FIG. 1, the coupler load istransmitted through the butt end 16 to the follower and draft gear 22contained rearwardly of the coupler 10. In such a condition, the key 20remains unloaded, as shown in FIG. 1, with no buffing contact loadbetween the keyslot 18 and 20.

Referring now to FIG. 2 there is shown the standard coupler underpulling conditions wherein the coupler load is transmitted to the yokeand draft gear through the key 20 by means of the keyslot bearingsurface 24. When the pull on the coupler is straight, the coupler loadis distributed over the entire bearing surface 24. However, a horizontalangling of the coupler, as shown in FIG. 2,, results in angularity ofthe key 20 in the coupler keyslot 18. Under such conditions, the couplerload is then transmitted on the corner 26 of the keyslot 18 at thelocation where the keyslot l8 intersects the sidewall 28 of the coupler10 resulting in a severe peening of the comer 26 which may cause cracksand material failures to occur at this portion of the keyslot.

Referring now to FIG. 3 of the drawings there is shown the improvedcoupler keyslot bearing contour of the invention which comprises a firstare 30 formed rearwardly towards the butt end 16 of thecoupler 10. Thefirst are 30 terminates in a plurality of second arcs, shown generallyas the numeral 32, which terminate tangent to the sidewalls 28 of thecoupler shank 14. The first are 30 forming the key bearing surface ofthe keyslot 18 may be formed as an inner arc of a toroid having a radiuslying rearwardly from the butt end 16 of the coupler shank 14.

In the embodiment shown a radius of substantially 50 inches wouldencompass the normal range of the coupler angling to provide asubstantially constant stress pattern in the bearing surfaces to thecorner 26.

Referring now to FIG. 4 in particular, there is shown in an enlargedsectional view one of the plurality of second arcs 32 shown in FIG. 5 ofthe drawings, at the respective sidewalls 28 of the coupler shank 14.When the second arcs 32 are formed in this manner, the possibility ofundercutting of the sidewalls is eliminated should the keyslot coreshift along its axis during the pouring process.

In the embodiment shown in FIG. 4 the grooves 36 are completed by aplurality of radii 38 terminating at the sidewalls 28 of the couplershank 14. A preferred dimension for radius 34 would be substantiallythree-eight of an inch and preferred dimension for the radius 38 wouldbe substantially 1 inch.

In addition to the toroidal shape of the key bearing surface 24 of theinvention, the surface may also be formed in the shape of otherrearwardly extending first arcs, such as an elliptic segment, aparabolic segment or a hyperbolic segment, to name a few, all of whichwould terminate in he plurality of second arcs 32 without departing fromthe spirit and scope of the invention. When the key bearing surface isprovided with the toroidal shaped are or other arcs having rearwardlyextending configurations, it can be seen that improved couplerperformance is obtained during pulling conditions resulting in providingmore bearing area at the corner 26 of the keyslot 1% thereby providingfor coupler angularity.

Referring now to FIG. 6 there is shown a modification of the improvedkeyslot bearing contour of the invention wherein the second arcs of theinvention are formed by the radii 41), one of which is located on eachside of the coupler keyslot. The radii d0 forms the second arcs of theinvention and initiate at the termination of the first arc 30 andterminate tangent to a line parallel to the coupler sidewall 28, saidline lying outside the coupler sidewall.

When the second arcs are formed in this manner the plurality of groovesshown in the embodiment of FIGS. 3, i and 5 would not be used and inplace thereof would be formed a small amount of metal 42 outside of thesidewall 28 that could be removed by grinding. The amount of the metal42 is sufficient to accommodate tolerances necessary in setting the corewithout obtaining excessive undercut of the sidewall 28 in case thekeyslot core shifts along its axis during the pouring process. it hasbeen found that when the radius 40 is approximately three eight of aninch that the maximum undercut of the sidewall 28 will be one-sixteenthof an inch.

From the foregoing it can be seen that an improved new and novel couplerkeyslot bearing contour, as shown in the embodiment of FIG. 3 or themodification of FIG. 6, has been provided, which minimizes the localizedbearing on the keyslot bearing surface during an angular pull on thecoupler. This has been accomplished by the novel use of a first arc anda plurality of second arcs formed in the manner hereinbefore described.While all of the objects and advantages of the invention have beenprovided for in the embodiment and modification shown, it is apparentthat many changes in details of construction may be made withoutdeparting from the spirit and scope of the invention, which is expressedin the accompanying claims and the invention is not to be limited to heexact matters shown and described since only the preferred embodimenthas been given by way of illustration only.

lclaim:

l. in a railroad coupler shank of the type having a horizontal keyslotforming a key bearing surface through the butt end of the coupler shank,the improvement comprising:

a. the key bearing surface being formed in the shape of a rearwardlyextending first arc; and

b. a plurality of second arcs tangent to the coupler shank walls andsaid first are and formed at the intersection of said first arc and thecoupler sidewalls, said first and second arcs serving to minimize thelocalized bearing on the keyslot of the coupler shank during angularpull of the coupler.

2. The improvement as defined in claim 1 wherein said first arccomprises an inner arc of a toroid having a radius lying rearwardly fromthe butt end of the shank.

3. The improvement as defined in claim 1 wherein said second arcs areformed by means of the sidewalls having formed therein a plurality ofvertical grooves extending the height of the sidewalls and located atthe intersection of said first arc and the sidewalls.

4. In a railroad coupler shank of the type having a horizontal keyslotforming a key bearing surface through the butt end of the coupler shank,the improvement comprising the key bearing surface being formed in theshape of a rearwardly extending elliptic segment terminating in aplurality of second arcs at the intersection of the sidewalls and thekey bearing surface for minimizing the localized bearing on the keyslotduring angular coupler pull.

5. The improvement as defined in claim 4 wherein each of said secondarcs are formed by a vertical groove formed in the related sidewall andlocated at the intersection of the key bearing surface and the relatedsidewall.

6. The improvement as defined in claim 4, wherein each of said secondarcs is defined at a portion thereof rearwardly of said segment by apair of radii and is defined forwardly of said segment by another pairof radii longer than said first-mentioned radii.

7. In a railroad coupler shank of the type having a horizontal keyslotforming a key bearing surface through the butt end of the coupler shank,the improvement comprising:

a. the key bearing surface being formed in the shape of a rearwardlyextending first arc; and

b. a plurality of second arcs initiated at the termination of said firstarc and terminating tangent to a line parallel to the coupler sidewall,said line lying outside of the sidewall, said first and second arcsserving to minimize the localized bearing on the keyslot of the couplershank during angular pull of the coupler.

8. The improvement as defined in claim 7 wherein said first arccomprises an inner arc of a toroid having a radius lying rearwardly fromthe butt end of the shank.

. In a railroad coupler shank of type having a horizontal keyslotforming a key bearing surface through the butt end of the coupler shank,the improvement comprising the key bearing surface being formed in theshape of a rearwardly extending elliptic segment terminating in at leasttwo second arcs, located on each side of the coupler sidewall, saidsecond arcs terminating tangent to a line which lies parallel to thecoupler sidewall and outside of the sidewall, said first and second arcsserving to minimize the localized bearing on the keyslot during angularcoupler pull.

1. In a railroad coupler shank of the type having a horizontal keyslotforming a key bearing surface through the butt end of the coupler shank,the improvement comprising: a. the key bearing surface being formed inthe shape of a rearwardly extending first arc; and b. a plurality ofsecond arcs tangent to the coupler shank walls and said first arc andformed at the intersection of said first arc and the coupler sidewalls,said first and second arcs serving to minimize the localized bearing onthe keyslot of the coupler shank during angular pull of the coupler. 2.The improvement as defined in claim 1 wherein said first arc comprisesan inner arc of a toroid having a radius lying rearwardly from the buttend of the shank.
 3. The improvement as defined in claim 1 wherein saidsecond arcs are formed by means of the sidewalls having formed therein aplurality of vertical grooves extending the height of the sidewalls andlocated at the intersection of said first arc and the sidewalls.
 4. In arailroad coupler shank of the type having a horizontal keyslot forming akey bearing surface through the butt end of the coupler shank, theimprovement comprising the key bearing surface being formed in the shapeof a rearwardly extending elliptic segment terminating in a plurality ofsecond arcs at the intersection of the sidewalls and the key bearingsurface for minimizing the localized bearing on the keyslot duringangular coupler pull.
 5. The improvement as defined in claim 4 whereineach of said second arcs are formed by a vertical groove formed in therelated sidewall and located at the intersection of the key bearingsurface and the related sidewall.
 6. The improvement as defined in claIm4, wherein each of said second arcs is defined at a portion thereofrearwardly of said segment by a pair of radii and is defined forwardlyof said segment by another pair of radii longer than saidfirst-mentioned radii.
 7. In a railroad coupler shank of the type havinga horizontal keyslot forming a key bearing surface through the butt endof the coupler shank, the improvement comprising: a. the key bearingsurface being formed in the shape of a rearwardly extending first arc;and b. a plurality of second arcs initiated at the termination of saidfirst arc and terminating tangent to a line parallel to the couplersidewall, said line lying outside of the sidewall, said first and secondarcs serving to minimize the localized bearing on the keyslot of thecoupler shank during angular pull of the coupler.
 8. The improvement asdefined in claim 7 wherein said first arc comprises an inner arc of atoroid having a radius lying rearwardly from the butt end of the shank.9. In a railroad coupler shank of type having a horizontal keyslotforming a key bearing surface through the butt end of the coupler shank,the improvement comprising the key bearing surface being formed in theshape of a rearwardly extending elliptic segment terminating in at leasttwo second arcs, located on each side of the coupler sidewall, saidsecond arcs terminating tangent to a line which lies parallel to thecoupler sidewall and outside of the sidewall, said first and second arcsserving to minimize the localized bearing on the keyslot during angularcoupler pull.